E-screen Assay Research Articles

Enhancing solar disinfection (SODIS) with the photo-Fenton or the Fe2+/peroxymonosulfate-activation process in large-scale plastic bottles leads to toxicologically safe drinking water

Solar disinfection (SODIS) in 2-L bottles is a well-established drinking water treatment technique, suitable for rural, peri‑urban, or isolated communities in tropical or sub-tropical climates. In this work, we assess the enlargement of the treatment volume by using cheap, large scale plastic vessels. The bactericidal performance of SODIS and two solar-Fe2+ based enhancements, namely photo-Fenton (light/H2O2/Fe2+) and peroxymonosulfate activation (light/PMS/Fe2+) were assessed in 19-L polycarbonate (PC) and 25-L polyethylene terephthalate (PET) bottles, in ultrapure and real water matrices (tap water, lake Geneva water). Although SODIS always reached total (5-logU) inactivation, under solar light, enhancement by or both Fe2+/H2O2 or Fe2+/PMS was always beneficial and led to an increase in bacterial elimination kinetics, as high as 2-fold in PC and PET bottles with tap water for light/H2O2/Fe2+, and 8-fold in PET bottles with Lake Geneva water. The toxicological safety of the enhancements and their effects on the plastic container materials was assessed using the E-screen assay and the Ames test, after 1-day or 1-week exposure to SODIS, photo-Fenton and persulfate activation. Although the production of estrogenic compounds was observed, we report that no treatment method, duration of exposure or material resulted in estrogenicity risk for humans, and similarly, no mutagenicity risk was measured. In summary, we suggest that SODIS enhancement by either HO•- or SO4•−-based advanced oxidation process is a suitable enhancement of bacterial inactivation in large scale plastic bottles, without any associated toxicity risks.

In vitro estrogen-disrupting effects of organophosphate flame retardants

Organophosphate flame retardants (OPFRs), as substitutes for polybrominated diphenyl ethers (PBDEs), are frequently detected in the environment and biota due to their widespread use. Thus, there is a need to investigate their potential estrogen-disrupting effects and possible mechanisms of action in an effort to obtain a better risk assessment. In this study, we characterized the activities on estrogen receptor α (ERα) and the estrogen-disrupting potential of fourteen OPFRs, TMP, TEP, TPP, TnBP, TiBP, THP, TPhP, TCP, DPK, MDPP, IDPP, CDP, IPPDP and MPhP, using three in vitro assays representing different specific modes of action (MoAs). In the yeast two-hybrid assay, no OPFRs induced agonistic activity, but TiBP, DPK, TPhP, MDPP, CDP and IPPDP were shown to be hydrophobicity-dependent antagonists and to compete with E2 for binding to ERα. In the MVLN cell assay, TPhP was the only OPFR among the 14 tested that was able to activate ERα-estrogen responsive element (ERE) pathways. The results from the E-SCREEN assay showed that all tested OPFRs except TMP had estrogenic properties, and G protein-coupled receptor 30 (GPR30) was involved in the estrogenicity of eight OPFRs, TiBP, THP, TPhP, TCP, MDPP, IPPDP, CDP and MPhP. It was also found that in the E-SCREEN assay, the estrogenicity of alkyl-OPFRs but not aryl-OPFRs was closely correlated to hydrophobicity. Our research suggested that most OPFRs were estrogen disruptors, but their related mechanisms were complex and might involve ERα-mediated and/or ERα-independent pathways. Further in vitro studies concerning the estrogenic effects and involved mechanisms of OPFRs, as well as comprehensive evaluations of OPFRs including health and ecological assessments are needed to determine whether they are safe substitutes for PBDEs.

Reproductive Performance of Mares Fed Dietary Zearalenone.

It is known that zearalenone (ZON) interacts directly with estrogen receptors, and its in vivo effects on reproduction have been well-documented in several species. In contrast, reports of ZON's impact on horse reproduction are conflicting and inconclusive, some studies confounded by the presence of mycotoxins such as deoxynivalenol in the feed. This study assesses the effect of chronic consumption of zearalenone on reproduction in cycling mares fed >95% pure ZON (0, 2, or 8 mg/da; n = 7 mares/treatment) for three estrous cycles, followed by artificial insemination, through 16 days of pregnancy. Animals were on ZON treatment for between 70 and 121 days (average 84) depending on individual cycle patterns. ZON-induced changes in serum concentration of estradiol (E2) and progesterone (P4), and total estrogenicity were measured using RIAs and the E-screen assay, respectively. Effects on reproductive physiology and pregnancy were monitored by ultrasound and clinical parameters. No significant changes were found in reproductive hormone levels of E2, or P4 for mares on ZON treatments compared to controls, although there was a significant (P < 0.01) increase in P4 levels across Cycle number in High ZON (8 mg/da) treated mares. There was also an increasing trend in the interovulatory interval in the High ZON treatment group. The overall estrogenicity was similar across treatments and over time, not differing from controls or between ZON treatment groups. Adverse uterine and ovarian effects were also not observed, but pregnancy rates were mixed with only 4 of 7 mares on Low ZON becoming pregnant, and only 3 maintaining pregnancy and fetal heartbeat by Day 30, compared to 5 of 6 control mares and all 7 mares on High ZON. Because reproductive efficiency and hormone concentrations are highly variable across individuals, this study did not demonstrate that ZON at 2 or 8 mg/da was detrimental to mares' reproduction. Yet, inferring that ZON treatments were completely without effect is also not appropriate, as the absence of measurable significant differences could be attributed to the limited sample size. Most importantly, there were no extreme signs of toxicology, in contrast to previous reports when ZON was fed at these “doses.”

Concentrations of bisphenol A and parabens in socks for infants and young children in Spain and their hormone-like activities

BackgroundLittle information is available on the content of bisphenol A (BPA) and other endocrine-disrupting chemicals (EDCs) such as parabens in infant textiles and clothes. Objectives1) To determine the concentrations of BPA and parabens in socks for infants and young children purchased in Spain, 2) to assess the (anti-)estrogenicity and (anti-)androgenicity of extracts from the socks, and 3) to estimate dermal exposure doses to these chemicals. MethodsThirty-two pairs of socks for infants and young children (1–48 months) were purchased from 3 stores in Granada (Spain). Textile material was cut from the foot, toe, and leg of each sock (n = 96 samples) for chemical analysis. Hormone-like activities were determined in foot sections (n = 32 samples) by using the E-Screen assay for (anti-)estrogenicity and PALM luciferase assay for (anti-)androgenicity. ResultsBPA was present in 90.6% of samples at concentrations ranging from <0.70 to 3736 ng/g. BPA levels were around 25-fold higher in socks from store 1, which had a higher cotton content compared to stores 2 and 3. Ethyl-paraben was found in 100% of samples, followed by methyl-paraben (81.0%), and propyl-paraben (43.7%). No butyl-paraben was detected in any sample. Estrogenic activity was detected in 83.3% of socks from store 1 (range = 48.2–6051 pM E2eq/g) but in only three socks from stores 2 and 3. Anti-androgenic activity was detected in six of the 32 socks studied (range = 94.4–2989 μM Proceq/g), all from store 1. Estimated dermal exposure to BPA was higher from socks for children aged 36–48 months (median = 17.6 pg/kg/day), and dermal exposure to parabens was higher from socks for children aged 24–36 months (median = 0.60 pg/kg/day). DiscussionThis is the first report in Europe on the wide presence of BPA and parabens in socks marketed for infants and children. BPA appears to contribute to the hormone-like activity observed in sock extracts.

Estrogenic Activity of Sanguiin H-6 through Activation of Estrogen Receptor α Coactivator-binding Site

A popular approach for the study of estrogen receptor α inhibition is to investigate the protein-protein interaction between the estrogen receptor (ER) and the coactivator surface. In our study, we investigated phytochemicals from Rubus coreanus that were able to disrupt ERα and coactivator interaction with an ERα antagonist. The E-screen assay and molecular docking analysis were performed to evaluate the effects of the estrogenic activity of R. coreanus extract and its constituents on the MCF-7 human breast cancer cell line. At 100 μg/mL, R. coreanus extract significantly stimulated cell proliferation (574.57 ± 8.56%). Sanguiin H6, which was isolated from R. coreanus, demonstrated the strongest affinity for the ERα coactivator-binding site in molecular docking analysis, with a binding energy of -250.149. The initial results of the study indicated that sanguiin H6 contributed to the estrogenic activity of R. coreanus through the activation of the ERα coactivator-binding site.

Sesquiterpenes from Cyperus rotundus and 4α,5α-oxidoeudesm-11-en-3-one as a potential selective estrogen receptor modulator

Estrogenic activity-oriented fractionation and purification of methanol extract from the rhizome of Cyperus rotundus, a well-known traditional herbal medicine, led to the isolation of six sesquiterpenes. 4α,5α-Oxidoeudesm-11-en-3-one (2) and cyper-11-ene-3,4-dione (3) together with four known sesquiterpenes, cyperotundone (1), caryophyllene α-oxide (4), α-cyperone (5), and isocyperol (6) were obtained from the hexane and dichloromethane fractions. Compounds 2 and 3 were newly isolated from natural resources in particular. To identify the possible use of isolated compounds as an alternative to hormone replacement therapy (HRT), estrogenic activity was evaluated by E-screen assay on MCF-7 BUS cells. Among the all isolated compounds from the rhizome of Cyperus rotundus, newly isolated from natural resource, 2 exhibited the most potent estrogenic activity. In an estrogen sensitive reporter gene assay, 2 significantly increased transcriptional activities. As a phytoestrogen, 2 was assessed by investigating dual action on ER-α and ER-β in competitive binding assay. It was found that 2 exerted higher binding affinity to ER-β than ER-α and it also showed both estrogenic and antiestrogenic effects depending on the E2 concentration. Our results indicate that newly isolated from Cyperus rotundus, 2 has biphasic activities on estrogen receptors which could be useful as an alternative HRT.

Dual effects of isoflavonoids from Pueraria lobata roots on estrogenic activity and anti-proliferation of MCF-7 human breast carcinoma cells

Pueraria lobata root (PLR), well known as Kudzu root, has recently become commercially available in Western dietary supplements for menopausal symptoms. The scientific basis for its action has been attributed to the action of phytoestrogens. This study aimed to investigate the estrogen-like activity of isoflavonoids isolated from P. lobata root and their safety with respect to their effect on breast cancer cell proliferation. In an E-screen assay, crude MeOH extract of PLR significantly increased the proliferation of MCF-7 cells in a concentration-dependent manner. Among the four fractions obtained by solvent fractionation of MeOH extract, the n-BuOH fraction had significant estrogen-like activities at all concentrations tested. Phytochemical analysis of the n-BuOH fraction led to the isolation of 10 isoflavones (1–10), among which genistein (10) had significant estrogen-like activities at all concentrations tested. These activities were significantly enhanced by treatment with genistein and 17β-estradiol compared with 17β-estradiol alone, and this effect was mediated by decreased expression of estrogen receptor (ER)α and phospho-ERα in MCF-7 cells. In a cell cytotoxicity assay, genistein (10) exhibited significant cytotoxicity in both ER-positive MCF-7 and ER-negative MDA-MB-231 breast cancer cells. This cytotoxicity was characterized by the induction of apoptotic cells stained with annexin V conjugated with Alexa Fluor 488 and involved activation of mitochondria-independent and -dependent apoptosis pathways in MCF-7 cells. Our results demonstrated that genistein (10) has estrogen-like effects dependent on ER pathway activation and anti-proliferative effects mediated by the apoptosis pathway rather than the ER pathway in MCF-7 breast cancer cells.

In Vitro Estrogenic and Breast Cancer Inhibitory Activities of Chemical Constituents Isolated from Rheum undulatum L.

We investigated the estrogenic and breast cancer inhibitory activities of chemical constituents isolated from Rhei undulati Rhizoma (roots of Rheum undulatum L.), which is used as a laxative, an anti-inflammatory, and an anti-blood stagnation agent. Estrogen-like activity was studied using the well characterized E-screen assay in estrogen receptor (ER)-positive MCF-7 cells. The mechanism underlying the breast cancer inhibitory activity of the compounds was studied using human ER-negative MDA-MB-231 and ER-positive MCF-7 cells. The activation of apoptosis pathway-related proteins was investigated by western blotting, using extracts of R. undulatum prepared in three solvent conditions (EX1, EX2, and EX3). The R. undulatum chemical constituents (compounds 1–3) showed estrogen-like activity in the concentration range of 10 to 50 μM, by increasing the proliferation of human ER-positive MCF-7 cells. These effects were attenuated by co-treatment with 100 nM fulvestrant, an ER antagonist. Compounds 1–3 decreased the viability of MCF-7 cells in a concentration-dependent manner. Compounds 1 (aloe emodin) and 2 (rhapontigenin) induced mitochondria-independent apoptosis by activating the caspase-8 pathway, whereas the cytotoxic effect of compound 3 (chrysophanol 1-O-β-d-glucopyranoside) was mediated through the mitochondria-dependent apoptotic pathway.

Estrogenic activity of zearalenone, α-zearalenol and β-zearalenol assessed using the E-screen assay in MCF-7 cells

Mycotoxins, including zearalenone (ZEA), can occur worldwide in cereals. They can enter the food chain and cause several health disorders. ZEA and its derivatives (α-zearalenol, α-ZOL and β-zearalenol, β-ZOL) have structural analogy to estrogen, thus they can bind to estrogen receptors (ERs). In order to characterize the estrogenic activity of ZEA, α-ZOL and β-ZOL, the proliferation of ER-positive human breast cancer cells (MCF-7) exposed to these mycotoxins was measured. After exposure at levels ranging from 6.25 to 25 µM, cell proliferation was evaluated by using the E-Screen bioassay. In accordance with previous studies, our results show the estrogenic activity of ZEA, α-ZOL and β-ZOL in MCF-7 cells. This effect is related to ZEA and its metabolites being flexible enough to bind to mammalian ERs. The relative proliferative effect (RPE) ranged from 10% to 91%. The α-ZOL induced the highest proliferative effect due to its higher affinity for the ERs compared to the other mycotoxins.

Interactions between plant-derived oestrogenic substances and the mycoestrogen zearalenone in a bioassay with MCF-7 cells.

Human and animal diets may contain several non-steroidal oestrogenic compounds which originate either from plants (phytoestrogens) or from fungi that infect plants (mycoestrogens such as zearalenone (ZEN)). Phytoestrogens may compete with ZEN in binding to the oestrogen receptor β and thereby may counteract the oestrogenic activity of ZEN. Using a modified version of the E-screen assay, plant-derived oestrogenic substances were tested for their proliferative or anti-proliferative effect on oestrogen-dependent MCF-7 cells. The samples were additionally tested for their ability to influence the oestrogenic activity of ZEN (1 μM). Among the individual substances tested, 8-prenylnaringenin had the strongest effect, as cell proliferation was increased by 78% at the lowest concentration (0.23 μM), and by 167% at the highest concentration (29.4 μM). Coumestrol (5.83 μM) increased cell proliferation by 39%, and genistein (370 μM) by 61%, respectively. Xanthohumol and enterolactone did not stimulate cell proliferation significantly. In the co-incubation experiments with ZEN, none of the single substances was able to decrease the oestrogenic activity of ZEN. Only for 8-prenylnaringenin (14.7 and 29.4 μM) was a trend towards an increase in the ZEN-induced cell proliferation up to 72% observed. In conclusion, with the exception of 8-prenylnaringenin, no substantial interaction between phytoestrogens and the mycotoxin ZEN could be detected using a bioassays with MCF-7 cells.

Advanced treatment of landfill leachate membrane concentrates: performance comparison, biosafety and toxic residue analysis.

With the improvement of people's consciousness about health, more attention has been paid to the biosafety of effluent reaching conventional discharge standard. In this contribution, removal efficiency of chemical oxygen demand (COD), acute toxicity, genotoxicity and estrogenicity in landfill leachate membrane concentrates (MCs) among UV-Fenton, Fenton and activated carbon adsorption process were compared. Daphnia magna acute toxicity assay, comet assay, cytokinesis-block micronucleus and E-screen assay were performed to assess whether the effluent reaching the main parameters of Chinese Discharge Standard (GB 16889-2008) still had toxic residues. Under the conditions that COD of effluents treated by the three processes were up to the discharge standard, no obvious toxic residue was found in the effluent of UV-Fenton treatment, but effluent from Fenton or activated carbon adsorption process showed genotoxicity or estrogenicity to some extent. Dynamic analysis of UV-Fenton degradation process for estrogen simulation solutions was also conducted, and the formation of intermediates was detected by gas chromatography-mass spectrometry (GC/MS). Toxic residues might be caused by the lack of treatment duration and the formation of more toxic intermediates. UV-Fenton was found to be efficient for the treatment of MCs. Biosafety should be concerned when a new wastewater discharge standard is being established.

Estrogen-like and tissue-selective effects of 7-methoxycoumarin from Ficus umbellata (Moraceae): an in vitro and in vivo study

BackgroundFicus umbellata is a medicinal plant previously shown to endow estrogenic properties. Its major component was isolated and characterized as 7-methoxycoumarin (MC). Noteworthy, coumarins and the respective active metabolite 7-hydroxycoumarin analogs have shown aromatase inhibitory activity, which is of particular interest in the treatment of estrogen-dependent cancers. The present work aimed at evaluating the estrogenic/antiestrogenic effects of MC in vitro and in vivo.MethodsTo do so, in vitro assays using E-screen and reporter gene were done. In vivo, a 3-day uterotrophic assay followed by a postmenopausal-like rat model to characterize MC as well as F. umbellata aqueous extract in ovariectomized Wistar rats was performed. The investigations focused on histological (vaginal and uterine epithelial height) and morphological (uterine wet weight, vagina stratification and cornification) endpoints, bone mass, biochemical parameters and lipid profile.ResultsMC induced a significant (p < 0.05) MCF-7 cell proliferation at a concentration of 0.1 μM, but did not inhibit the effect induced by estradiol in both E-screen and reporter gene assays. In vivo, MC treatment did not show an uterotrophic effect in both rat models used. However, MC (1 mg/kg) induced a significant increase (p < 0.01) of vaginal epithelial height. No significant change was observed with MC in abdominal fat weight, serum lipid levels and bone weight.ConclusionThese results suggest that MC has a weak estrogenic activity in vitro and in vivo that accounts only in part to the estrogenicity of the whole plant extract. MC could be beneficial with regard to vagina dryness as it showed a tissue specific effect without exposing the uterus to a potential tumorigenic growth.

Halogenated 17β-Estradiol Surrogates: Synthesis, Estrogenic Activity, and Initial Investigations of Fate in Soil/Water Systems.

17β-Estradiol (E2), a natural, endocrine-disrupting, steroid hormone, is excreted by all vertebrates and can enter the environment from domestic animal and wildlife wastes. Multiple field studies using livestock manures as E2 sources suggest significant background concentrations of E2 (e.g., wildlife sources, hydrolysis of E2 conjugates, previous inputs). To accurately understand field fate and transport processes of E2, it is necessary to address the issue of background detections. In this study, two fluorinated and three brominated surrogate compounds of E2 were synthesized and compared to native E2 using soil/water batch experiments and for estrogenic activity. Analytical difficulties presented by the two fluorinated congeners deemed these compounds to be unsuitable surrogates of E2, and further assessment was abandoned. However, the brominated congeners proved promising, with log( ) values that fell within the range previously reported for E2. Batch studies yielded similar relative aqueous concentrations and linear sorption isotherms across time for E2 and 2-bromo-17β-estradiol; however, the relative aqueous concentrations and linear sorption isotherms of 4-bromo-17β-estradiol and 2,4-dibromo-17β-estradiol were different from E2 but similar to one another. All three brominated congeners possessed estrogenic activity by E-Screen assay, albeit three orders of magnitude less than native E2, putatively due to steric interference introduced by the large bromine atom on the phenolic ring, the group that mediates interaction with the estrogen receptor. The data suggest that 2-bromo-17β-estradiol may serve as a suitable surrogate for E2 in planned field scale tracer studies designed to distinguish between antecedent and de novo inputs.

E-screen assay validation: evaluation of estrogenic activity by MCF7 cell culture bioassay, in drinking water from different watersheds in state of São Paulo, Brazil

E-screen assay validation: evaluation of estrogenic activity by MCF7 cell culture bioassay, in drinking water from different watersheds in state of São Paulo, Brazil

Estrogenic activity of zinc pyrithione: an in vivo and in vitro study.

Zinc pyrithione (ZP) is commonly used to prevent dandruff and seborrheic dermatitis. Many consumers are exposed daily to high doses of ZP, causing serious concerns about its toxicity. The reproductive and developmental toxicities were previously reported in pregnant rats. However, the estrogenic activity of ZP at varying degrees of exposure has been rarely studied. Thus, we performed an uterotrophic assay, E-screen assay, and gene expression profiling to assess the estrogenic activity of ZP. For the uterotrophic assay, ZP (2, 10, or 50 mg/kg/d) was subcutaneously administered to ovariectomized rats every day for three days. Uteri were extracted 24 hours after the last dose. Then, wet and blotted uterine weights were measured. For the E-screen essay, MCF-7 cells (a breast cancer cell line) were exposed to 10-9 to 10-6 M of ZP, and cell proliferation was then measured. For the gene expression analysis, changes of gene expression levels in uterine samples taken for the uterotrophic assay were analyzed. In the uterotrophic assay, the concentration of ZP had no significant effect on uterine weight. In the E-screen assay, ZP at any concentration showed no significant increase in MCF-7 cell proliferation, compared to the control group. However, 10-6 M of ZP significantly reduced cell viability. The changes in gene expression slightly differed between the ZP and control groups. The in vivo and in vitro assays, together with gene expression analysis, demonstrated that ZP showed no significant estrogenic activity.

Ethanol-extracted Cameroonian propolis exerts estrogenic effects and alleviates hot flushes in ovariectomized Wistar rats

BackgroundSince the biological properties of propolis depend to the plants that can be found in a specific region, propolis from unexplored regions attracts the attention of scientists. Ethanolic extract of Cameroonian propolis (EEP) is used to treat various ailments including gynecological problems and amenorrhea. Since there were no scientific data to support the above claims, the present study was therefore undertaken to assess estrogenic properties of Cameroonian propolis.MethodsTo achieve our goal, the ability of EEP to induce MCF-7 cells proliferation in E-screen assay as well as to activate estrogen receptors α (ERα) and β (ERβ) in cell-based reporter gene assays using human embryonic kidney cells (HEK293T) transfected with ERs was tested. Further, a 3-day uterotrophic assay was performed and the ability of EEP to alleviate hot flushes in ovariectomized adult rats was evaluated.ResultsIn vitro, EEP showed an antiestrogenic activity in both HEK293T ER-α and ER-β cells. In vivo, EEP induced a significant increase in a bell shape dose response manner of the uterine wet weight, the total protein levels in the uterus, the uterine and vaginal epithelium height and acini border cells of mammary gland with the presence of abundant eosinophil secretions. Moreover, EEP induced a significant decrease in the total number, average duration as well as frequency of hot flushes after 3 days of treatment in rat (equivalent to a month in woman). The dose of 150 mg/kg exhibited the most potent estrogenic effects among all the tested doses. The UPLC-HRMS analysis showed the presence of caffeic acid derivatives and trirtepernoids in EEP, which are well known endowed with estrogenic properties.ConclusionThese results suggest that Ethanolic extract of Cameroonian propolis has estrogen-like effects in vivo and may alleviate some menopausal problems such as vaginal dryness and hot flushes.Graphical abstractEthanol-extracted Cameroobian propolis exhibited in vitro and in vivo estrogen-like effects. This extract may contain promising phytoestrogens.

Evidence of Absence: Estrogenicity Assessment of a New Food-Contact Coating and the Bisphenol Used in Its Synthesis.

Consumer concerns about exposure to substances found in food contact materials with estrogenic activity (EA) have created substantial demand for alternatives. We assessed the potential EA of both a new bisphenol monomer used to synthesize polymeric coatings for metal food-contact applications and the nonintentionally added substances (NIAS) that may migrate into food. We evaluated tetramethyl bisphenol F (TMBPF) using in vitro and in vivo assays. We extracted the polymeric coating using food simulants ethanol (50% v/v) and acetic acid (3% w/v) and measured migration using tandem liquid chromatography (LC)/mass spectrometry (MS) and LC time-of-flight MS for TMBPF and NIAS, respectively. We also tested migrants for EA using the E-SCREEN assay. TMBPF did not show estrogenic activity in the uterotrophic assay and did not alter puberty in male and female rats or mammary gland development in female rats. Neither TMBPF nor the migrants from the final polymeric coating increased proliferation of estrogen-sensitive MCF7 cells. TMBPF did not show estrogen-agonist or antagonist activity in the estrogen receptor-transactivation assay. TMBPF migration was below the 0.2 parts per billion detection limit. Our findings provide compelling evidence for the absence of EA by TMBPF and the polymeric coating derived from it and that human exposure to TMBPF would be negligible.

Lannea acida A. Rich. (Anacardiaceae) Ethanol Extract Exhibits Estrogenic Effects and Prevents Bone Loss in an Ovariectomized Rat Model of Osteoporosis.

Phytoestrogens have been shown to prevent postmenopausal osteoporosis. Lannea acida is a medicinal plant traditionally used in Cameroon to treat infertility, gynaecological complaints, and rheumatism. These uses prompted us to evaluate estrogenic activity of Lannea acida bark ethanolic extract and its antiosteoporotic potential in ovariectomized Wistar rats. In vitro, the E-screen assay was used to assess the ability of L. acida extract to induce MCF-7 cells proliferation. In vivo, a 3-day uterotrophic assay and a 12-week oral treatment in ovariectomized adult rats were carried out to evaluate the ability of L. acida extract to prevent bone mass loss. L. acida extract induced MCF-7 cell proliferation. In vivo, it significantly increased the uterine wet weight, uterine and vaginal epithelial heights, and mammary glands differentiation. At 200 mg/kg, a long-term treatment with the extract prevented body weight gain (p < 0.05) and loss of bone mass and/or density (p < 0.05) induced by ovariectomy. Also, a significant (p < 0.001) decrease of alkaline phosphatase activity was observed with 50 mg/kg. L. acida extract improved bone microarchitecture and could restore normal bone mineralization by increasing the inorganic phosphorus and calcium level in bone. These findings provide evidence that Lannea acida is a potential alternative for the prevention of postmenopausal osteoporosis.

A ternary classification using machine learning methods of distinct estrogen receptor activities within a large collection of environmental chemicals.

Endocrine-disrupting chemicals (EDCs), which can threaten ecological safety and be harmful to human beings, have been cause for wide concern. There is a high demand for efficient methodologies for evaluating potential EDCs in the environment. Herein an evaluation platform was developed using novel and statistically robust ternary models via different machine learning models (i.e., linear discriminant analysis, classification and regression tree, and support vector machines). The platform is aimed at effectively classifying chemicals with agonistic, antagonistic, or no estrogen receptor (ER) activities. A total of 440 chemicals from the literature were selected to derive and optimize the three-class model. One hundred and nine new chemicals appeared on the 2014 EPA list for EDC screening, which were used to assess the predictive performances by comparing the E-screen results with the predicted results of the classification models. The best model was obtained using support vector machines (SVM) which recognized agonists and antagonists with accuracies of 76.6% and 75.0%, respectively, on the test set (with an overall predictive accuracy of 75.2%), and achieved a 10-fold cross-validation (CV) of 73.4%. The external predicted accuracy validated by the E-screen assay was 87.5%, which demonstrated the application value for a virtual alert for EDCs with ER agonistic or antagonistic activities. It was demonstrated that the ternary computational model could be used as a faster and less expensive method to identify EDCs that act through nuclear receptors, and to classify these chemicals into different mechanism groups.

Sorption and toxicity reduction of pharmaceutically active compounds and endocrine disrupting chemicals in the presence of colloidal humic acid.

This study investigated the toxicity changes and sorption of pharmaceuticals and endocrine disrupters in the presence of humic acid (HA). For the sorption experiment, a dead end filtration (DEF) system was used to separate bound and free-form target compounds. An algae growth inhibition test and E-screen assay were conducted to estimate the toxic effect of pharmaceutically active compounds (PhACs) and endocrine disrupting chemicals (EDCs), respectively. The permeate concentration was confirmed using liquid chromatography-mass spectrometry. In the sorption test, we observed significant sorption of PhACs and EDCs on colloidal HA, except for sulfamethoxazole (SMX). The values of log KCOC derived from DEF determinations ranged from 4.40 to 5.03. The removal efficiency varied with the HA concentration and the target chemical properties. Tetracycline and 4-octylphenol showed the highest sorption or removal efficiency (≈50%), even at 5 mg C/L HA. The algal growth inhibition of PhACs and the estrogenic effects of EDCs were significantly decreased in proportion to HA concentrations, except for SMX. In addition, the chemical analysis results showed a positive relationship with the bioassay results. Consequently, the sorption of PhACs and EDCs onto colloidal HA should be emphasized in natural environments because it significantly reduces bioavailable concentrations and toxicity to aquatic organisms.